Mitigation of GHE by carbon capture at NFCL,Kakinada.ppt
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The document discusses carbon capture and storage techniques used at the Nagarjuna Fertilizers and Chemicals Limited (NFCL) plant in Kakinada, India. NFCL uses natural gas as a feedstock to produce ammonia via steam methane reforming, capturing the CO2 byproduct for use in urea production. It also recovers CO2 from the flue gases of natural gas combustion using a carbon dioxide recovery plant. This recovered CO2 is also used to make urea, reducing greenhouse gas emissions. The techniques allow NFCL to mitigate emissions while continuing efficient urea production using natural gas as a feedstock and fuel source in fertilizer manufacturing.
Mitigation of GHE by carbon capture at NFCL,Kakinada.ppt
- 1. Mitigation of Green house emission by Carbon capture from Pre & Post Combustion of Natural gas and fixation to chemical fertilizer in a typical fertilizer industry Pradip Ghosh ,( M.Tech) , Petroleum Engineering branch
- 2. Green House Emission a possible cause for climate change Climate change is one of the key issues facing mankind today. Climate change is defined as, "change of climate that is attributed directly or indirectly to human activity that alters the composition of global atmosphere and which is in addition to natural climate variability observed over comparable time periods." The vast majority of climate change research strongly confirms a direct relation between human activity, the rising levels of greenhouse gases (GHG) in the atmosphere and Climate Change. A Greenhouse Gas (GHG) is a gas in an atmosphere that absorbs and emits radiation within the thermal infrared range. This process is the fundamental cause of the Greenhouse effect which is the prime contributor for Global Warming "Global warming" refers to the increase of the Earth's average surface temperature, due to a build-up of greenhouse gases in the atmosphere. Global Warming Potential (GWP) is a measure of how much a given mass of greenhouse gas is estimated to contribute to global warming. It is a relative scale which compares the gas with respect to CO2. The impacts of growing GHG emissions such as higher average temperature, rising sea water level, submerging of low-lying areas and unpredictable changes in climatic conditions.
- 3. Green House Emission a possible cause for climate change Importance of global climate Change Climate change is one of the most fundamental challenges ever to confront humanity. Its impacts are already showing and will intensify over time if left unchecked. There is overwhelming scientific evidence, as shown in the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC), that climate change will threaten economic growth and long-term prosperity, as well as the very survival of the most vulnerable populations. IPCC projections indicate that if emissions continue to rise at their current pace and are allowed to double from their pre-industrial level, the world will face an average temperature rise of around 3°C this century. Serious impacts are associated with this scenario, including sea-level rise, shifts in growing seasons, and an increasing frequency and intensity of extreme weather events such as storms, floods and droughts. The United Nations climate change negotiations offer a historical opportunity to step up international action on climate change. A comprehensive, ambitious and effective deal is essential to the global transition into green economic growth, and, most urgently, to help the world, especially the most vulnerable, adapt to impacts that are now inevitable.
- 4. Mitigation of GHE in a typical Fertilizer industry NFCL, Kakinada The integrated industrial facility of NFCL consists of 2×1350 Metric Tons per Day (MTPD) Ammonia plants based on Haldor Topsoe process technology and 2×2350 MTPD Urea plants based on Snamprogetti process technology along with all the required supporting facilities. NFCL, Kakinada started production back in 1992 from Unit-I (Ammonia-I & Urea-I) and in 1998 from Unit-II (Ammonia-II & Urea-II). It has two Ammonia manufacturing facilities – Ammonia I & Ammonia II. Both Ammonia Plants were designed for Natural Gas (NG) Feed Stock.NG is used in the Ammonia Plant both as feed & fuel. Most of the CO2 generated from reformation of NG feed will be usually recovered by using the conventional methods such as hot potash process, amine process etc and will be used in Urea production as raw material. Where as the CO2 generated by the combustion of NG as fuel in the furnace is normally not recovered and will be released into the atmosphere. NFCL installed a Carbon Dioxide Recovery (CDR) Unit to recover Carbon Dioxide from the reformer furnace flue gases to recover CO2 and thereby to maintain the same levels of Urea production instead of reforming excess NG in an increased (higher) capacity reformer. NFCL has therefore not only reduced CO2 emissions taking place due to reforming of NG feed but also reduced the emissions from NG firing as fuel in the reformer furnace. The 450 MTPD installed capacity CDR plant use to recover CO2 from flue gases of primary reformer of Ammonia Plant I and supply the recovered CO2 as raw material for Urea production. Thus, NFCl reduces fossil fuel consumption in Urea manufacturing process leading to direct reduction of Green house gas (GHG) emissions. The installation of the CDR plant would lead to estimated emission reductions of 82574 Ton of CO2 equivalent i.e. a total of 825740 Ton of CO2 over a ten year crediting period.
- 5. Carbon capture from Flue gas generated from post combustion of Natural gas at Primary Reformer & Fixation to Urea, A chemical Fertilizer at NFCL, Andhra Pradesh (India)
- 6. Carbon di oxide recovery plant at NFCL, Kakinada, Andhrapradesh
- 7. NFCL CDR Unit Layout Animation
- 8. CO2 Recovery process M/S NFCL implemented Carbon Dioxide Recovery unit to mitigate the CO2 emissions by CO2 recovery from flue gas stream (Post combustion of natural gas at furnace) for urea production, with the optimum use of Feedstock. CO2 Recovery process consists of following unit operations The CDR plant shall consist of three main sections; •Flue gas cooling section, •CO2 recovery section and •Solvent regeneration section. The following block flow diagram shows the plant configuration.
- 10. Process Description of Carbon Di Oxide recovery (CDR) Plant The raw flue gas enters the direct contact cooler where it is cooled from 190°C to 50°C. Prior to entering the absorber, the gas is compressed to 15.84 psia (1.113 Kg/cm2 abs). The cooled gas enters the absorber and flows up through the packed bed absorber counter current to the solvent solution. The solvent reacts chemically with the carbon dioxide in the absorber to remove 90% of the CO2 from the flue gas. The gas enters the wash section of the absorber at 145°F (63 °C) where water and solvent are removed and returned to the absorber packed section. The washed gas is vented to the atmosphere at 126°F (52°C). The rich solution leaves the absorber at 131°F (55°C) and is pumped to the lean/rich cross exchanger. In the cross exchanger the rich stream is heated to 237°F (114 °C). The carbon dioxide is removed from the rich solution in the stripper using a kettle type reboiler with 50 psig (3.5 kg/cm2, gauge) steam. Steam and solvent vapors leave the reboiler at 252 °F (122 °C) and enter the stripper below the packed section. The vapors move up the stripper condensing as the CO2 is liberated and the solvent solution is heated. Steam and carbon dioxide enter the wash section of the stripper where entrained solvent is removed.
- 11. The steam and carbon dioxide leave the stripper at 217°F (103°C) and enter the reflux condenser where steam is condensed and the carbon dioxide is cooled to 108°F (42 °C). The mixture then enters the reflux drum where carbon dioxide is separated from the condensate. The condensate is returned to the stripper as reflux. The lean solvent solution leaves the reboiler at 252°F (122 °C) and enters the cross exchanger where it is cooled. The lean solution is then pumped to the lean solvent cooler where it is further cooled to 108°F (42°C) by cooling water. A ten- percent side stream of the cool, lean amine solution goes through a carbon bed system to remove any of the solution contaminants. The produced CO2 is used for production of Urea.
- 12. Mitigation of GHE by Carbon capture from Pre combustion of Natural gas & fixation to chemical Fertilizer, Urea, A pathway to decarburization in a typical fertilizer industry, at NFCL, Andhra Pradesh (India)
- 13. Production of Syn gas for Ammonia manufacture by SMR process and fixation of by product CO2 as nitrogenous fertilizer Today most of us are aware how increased anthropogenic sources of CO2 emissions are affecting the global climatic conditions. Increased population, Energy usage & industrialization are enhancing the emission levels, which is affecting the Climate. Hence, adoption of advanced & cleaner technologies and use of best available feedstock is essential by the industries to control the emission levels. M/S NAGARJUNA FERTILISERS AND CHEMICALS LIMITED is South India’s first Natural Gas based fertilizer plant situated in Kakinada, Andhra Pradesh,a Urea manufacturing Fertilizer Unit,uses Natural Gas as feed stock for producing Syn gas for production of Ammonia via SMR process (Precombustion of Natural gas ) and CO2 as byproduct for urea manufacture.
- 14. A typical Urea manufacturing unit requires Ammonia & CO2 as raw materials. Ammonia is produced by the reaction of Hydrogen & Nitrogen. Hydrogen is produced from the steam reforming of Hydrocarbon Feedstock while the Nitrogen is extracted from atmospheric Air. In the Process of generating Hydrogen from Hydrocarbon Feedstock Carbon Dioxide will be generated as byproduct, which will be used as Raw material for Urea Production. Thus, both Ammonia & CO2 the required for Urea manufacture will be generated from Ammonia Plants. In a Urea manufacturing plant, Hydrocarbon Feedstock will be used as both feed & fuel. Hydrocarbon fuel will be used for processing hydrocarbon feedstock in to Hydrogen & CO2. Depending upon the characteristics of Feedstock, the generation of Ammonia & CO2 will vary. Urea reactor converts Ammonia and CO2 into urea solution. Unconverted urea solution is fed and decomposed into ammonia, water and carbon dioxide vapors at high pressures in the urea stripper, and recycled back to urea reactor. Overview of Carbon fixation process to UREA,a chemical Fertilizer at NFCL Kakinada Plant
- 15. Ammonia & Urea Manufacturing Facility at M/S Nagarjuna fertilizers & chemicals , Kakinada Andhrapradesh ( India )
- 16. SMR process for synthesis of Ammonia & byproduct CO2 General Process description of AMMONIA Production A useful description of the methane steam reforming process comprising the following steps: • Purification of the feedstock from reforming catalyst poisions; • Primary methane steam reforming • Secondary reforming, with the addition of air, conventionally called auto thermal reforming • Shift conversion of CO and H2O to produce syngas composing CO2 and H2; • Removal of CO2 from syngas • Methanation (a process that removes trace CO and CO2upon reaction with H2 in a reactor) • Synthesis of Ammonia Purification of the feedstock from reforming catalyst poisons The feed stock natural gas, is desulphurised by conversion of stable organic sulphur compounds into Hydrogen Sulphide in presence of Nickel Molybdenum catalyst R-SH + H2 R-H + H2S R-S-R1 + 2H2 H + R1-H + H2S R-S-S-R1 + 4H2 R-H + R1-H + 2H2S followed by absorption of Hydrogen Sulphide on Zinc Oxide bed ZNO + H2S ZNS + H2O
- 17. General Process Description of AMMONIA Production
- 18. The desulphurised natural gas is mixed with super heated steam to give steam to Carbon ratio of 3.3:1, preheated and fed to the catalyst tubes in Primary Reformer. The Primary Reformer is a side-fired furnace with radiant wall mounted burners. The natural gas which is predominantly methane undergoes following reactions producing Hydrogen and Carbon Oxides: CH4 + H2O 3 H2+ CO - Heat CO + H2O CO2 + H2 + Heat The process gas from the tubes is gathered by a collector system and sent to the Secondary Reformer. The Secondary Reformer is a refractory lined vessel containing Nickel catalyst. Air from atmosphere comes in contact with the process gas from Primary Reformer. Combustion of some part of Hydrogen and Methane occurs consuming the total oxygen in the air and the temperature rises to about 1300 deg. C. This supplies the heat needed for completion of the endothermic reaction in the catalyst bed. Nitrogen needed for ammonia synthesis gets introduced in to the system in the Secondary Reformer through the process air. The gas leaving Secondary Reformer contains residual Methane of 0.6%. The exit gas from Secondary Reformer is cooled to about 380 deg. C in the Waste Heat Boiler where high-pressure steam is generated. Primary & Secondary Methane steam reforming
- 19. Shift conversion to produce syngas The carbon monoxide formed in the reforming step is converted to CO2 by water gas shift reaction in two stages, namely, high temperature shift conversion and low temperature shift conversion. The HT shift reaction takes place in presence of iron oxide chromium oxide catalyst and LT shift reaction takes place in presence of copper oxide zinc oxide catalyst. The shift conversion reaction being exothermic, steam is produced by heat recovery. The reaction-taking place in the shift conversion can be represented as: CO + H2O CO2 + H2 + Heat The process gas leaving the CO conversion step contains in addition to Hydrogen and Nitrogen, large quantity of CO2 and small quantities of CO, Argon and Methane. Syn gas production by capturing CO2 by Giammarco Vetrocoke solution The CO2 present in the process gas is removed in the CO2 removal section using Giammarco Vetrocoke solution. The main constituents of GV solution are K2CO3, V2O5, DEA and GLYCINE ( NH2- CH2COOH),. V2O5 acts as the corrosion inhibiter and DEA, GLYCINE are the Activator & promoter of the reaction. H2O + CO2 H2CO3 K2CO3 + H2CO3 2KHCO3 ------------------------------- K2CO3 + H2O + CO2 -> 2 KHCO3 Here, CO2 absorbed in potassium Carbonate solution is regenerated by reducing the pressure and addition of heat in two stage regenerators. The regenerated solution is pumped back to the absorber.
- 20. Syn gas production by capturing CO2 by Giammarco Vetrocoke solution First Step reaction H2O + CO2 HCO3- + H+ H2O + CO3- HCO3- + OH- ----------------------------------- H2O + CO3- + CO2 2HCO3 Second Step reaction H2NCH2COO- + CO2 -OOCHNCH2COO- + H+ -OOCHNCH2COO- + H20 H2NCH2COO- + HCO3- ------------------------------------------------------------- CO2 + H2O HCO3- + H+ Thus, the system operates in closed circulation. The CO2 gas stripped from the solution in the regenerators is cooled and sent to Urea plant. Methanation to decarbonize syn gas The process gas exit absorber which contains only traces of CO and CO2, Since carbon oxides act as poison to the ammonia synthesis catalyst, the residual carbon oxides present in the process gas are converted into methane in a methanator reactor containing nickel catalyst. This step is the reverse of reforming reaction and consumes a small amount of hydrogen. CO + 3H2 CH4 + H20 CO2 + 4H2 CH4 + 2H20 CO + CO2 + 7H2 2CH4 + 3H20
- 21. Ammonia synthesis The Methanator exit gas after cooling and removal of condensate is the synthesis gas with some inert. This gas is compressed from 24 Kg/Cm2g to 134 Kg/Cm2g in a centrifugal syn gas compressor. Also, there is a recirculation stage in the compressor where the recycle of unconverted gas along with the compressed make up gas are further compressed to about 142 Kg/Cm2g. This gas after pre-heating is admitted to ammonia synthesis converter containing promoted iron catalyst, where Hydrogen and Nitrogen combine to form ammonia with evolution of heat. N2 + 3H2 2NH3 – Δ H Bird eye view of AMMONIA Plant at M/S Nagarjuna fertilizers & chemicals , Kakinada Andhra Pradesh ( India )
- 22. Carbon fixation as chemical Fertilizer,UREA Process description of UREA production The following operations are involved in the Urea process, • Urea Synthesis and high pressure recovery • Urea purification and low pressure recovery • Urea Concentration • Urea Prilling • Process Condensate Treatment Bird eye view of UREA Plant at M/S Nagarjuna fertilizers & chemicals , Kakinada ,Andhra Pradesh ( India )
- 23. General Process Description of UREA Production
- 24. Carbon Footprint Study of NFCL Complex, Kakinada In June 2008, the GoI released the National Action Plan on Climate Change, a policy document outlining a number of steps and measures that focus on achieving GHG mitigation and adaptation to climate change in ways that also promote the country’s development objectives. The National Plan discusses GHG mitigation options in the industry and ways to promote energy efficiency in residential & commercial sector. According to the Plan, CO2 emissions from fuel and electricity use in the industrial sector can be reduced by 16% in 2031 compared to the business as usual scenario. Carbon Footprint can be defined as a measure of the impact human activities have on the environment in terms of the amount of green house gases produced. In the case of an organization, business or enterprise, carbon footprint is the amount of C02 equivalent emitted as a part of their everyday operations. It is often expressed as tons of C02 or tons of carbon emitted, usually on an annual basis. With increasing importance to climate change and GHG issues, NFCL being an eco friendly industry, pursuing GHG management in a big way. The following are the drivers for compiling a GHG inventory and monitoring carbon footprint: • Managing GHG risks and identifying cost-effective reduction opportunities • Employee satisfaction and Public reporting • Participating in GHG markets and recognition for early voluntary action • Environmental co-benefits
- 25. Carbon Footprint Study of NFCL Complex, Kakinada Measurement of NFCL's GHG / Carbon Footprint: NFCL has taken the services of M/s CII, who have rich experience in the field of GHG emission monitoring; for developing the tool for estimation and Inventory Management of all GHG emissions within the Complex. NFCL & CII has explicitly adopted the 5 overarching accounting & reporting principles (Relevance, Completeness, Consistency, Transparency & Accuracy) highlighted in the GHG Protocol Corporate Standard for developing the Excel based tool for assessing present GHG emissions as well as for monitoring future business activities The following two measures were the prime contributors for NFCL Carbon Emission Intensity reduction by 21.3% from 2008-09 to 2009-10: • Installation of Carbon Dioxide Recovery Unit. This Unit recovers the CO2 from Fluegas, which is otherwise let to atmosphere. The CO2 thus recovered from this Unit is used for Urea production. • Changeover of entire Complex operations to Natural Gas mode.
- 26. Carbon Footprint Study of NFCL Complex, Kakinada The CDR project as implemented in NFCL plant, contributes positively to the “sustainable development of India” in following ways: Environmental well being: The project activity recovers CO2 from flue gases (which were earlier released to atmosphere) – resulting in positive environmental effects like reduction of GHG emissions. It also helps in conserving non-renewable resources like Naphtha and Natural gas, which can be used for important processes in future. Socio – economic well being: Project activity would marginally increase employment opportunity for semi-skilled, skilled labour and professionals in the region during construction and operation phase. Therefore contributing social well being aspects. The project will create a business opportunity for local stakeholders such as suppliers, contractors, bankers, etc. Moreover, the project will facilitate in enhancing the knowledge base and skills of employees of NFCL. Technological well being: The project uses “state-of-the–art” technology and will help the company to maintain its status of being one of the most progressive fertilizer companies in India by adopting the latest technology and its efforts for sustainability. The project implementation will aid in knowledge and skill development of the employees. Further, the project activity has good replication potential in other fertilizer plants of India and the world.
- 27. Classification of GHE GHG emission broadly be divided into three categories: The Primary GHG emissions / Footprint (Scope-1): It is a measure of direct emissions occurring due to activities owned and controlled by the organization. The Secondary GHG emissions / Footprint (Scope-2): It is a measure of indirect emissions occurring from purchase of various forms of energy. The Tertiary GHG emissions / Footprint (Scope-3): It is a measure of indirect emissions occurring from activities like business travel, travel of employees to office, outsourced activities, etc These are essentially activities earned out in premises or circumstances not owned, governed or controlled by the organization. Year 2008-09 2009-10 2010-11 Scope 1 0.624 0.487 0.479 Scope 2 0.002 0.002 0.001 Scope 3 0.01 0.012 0.011 Overall 0.636 0.501 0.492 % Reduction over Previous Year 21.3 1.8 NFCL’s Emission Intensity (MT CO2 Equivalent / MT Urea) 0.636 0.501 0.492 0.30 0.35 0.40 0.45 0.50 0.55 0.60 0.65 0.70 2008-09 2009-10 2010-11 Year CO2e Emissions, MT of CO2 / MT of Urea
- 28. Thank you